OCC has published a review on the Evercool Rifling Fan 80mm RF-8

The Evercool Rifling Fan RF-8 did respectably in testing, performing quieter than the case fans and performing as well as a fan with both a higher CFM and noise rating and in the load testing. The bearing is improved over sleeve bearing and has the second highest lifespan of Evercool's fans with 40,000 hours. The shape can be awkward, but if users want more performance out of a 80mm mount then this fan provides a solution. The fan performed well, but it does have some quirks.

Evercool Rifling Fan 80mm RF-8 Review